The present invention relates to a process for the preparation of C-pyrazine-methylamine compounds, and their conversion to 1,3-substituted-imidazo[1,5-a]pyrazines.
US 2006/0235031 discloses the preparation of C-pyrazine-methylamine compounds, which is different from the process of preparation according to the present invention. The process described in the above-identified application while suitable for the synthesis of small quantities is not ideal for large scale manufacture. Furthermore, the stability of the intermediates from the process in the above-identified publication also needs to be improved. See also U.S. Pat. No. 7,232,911.
There is desire for alternative and improved processes for the preparation of C-pyrazine-methylamine compounds, and their conversion to 1,3-substituted-imidazo[1,5-a]pyrazines with improved scalability, selectivity, efficiency, safety, reduced contamination, and cost.